Question Number 63857 by ajfour last updated on 10/Jul/19
Commented by ajfour last updated on 10/Jul/19
$${perfect}!\:{Sir}. \\ $$
Commented by mr W last updated on 10/Jul/19
$${s}_{{total}} =\frac{\mathrm{25}×\mathrm{5}}{\mathrm{3}}+\mathrm{60}×\mathrm{7}−\frac{\mathrm{35}×\mathrm{7}}{\mathrm{3}}=\mathrm{380}\:{m} \\ $$